Christian Raccurt

Pulmonary Colonization with Pneumocystis carinii in Human Immunodeficiency Virus-Negative Patients: Assessing Risk with Blood CD4 + T Cell Counts

Use of PCR analysis has led to detection of low numbers of Pneumocystis carinii organisms, which were undetectable by microscopy, in bronchoalveolar lavage (BAL) fluid specimens from immunosuppressed patients who showed no evidence of acute P. carinii pneumonia (PCP) (1). These low levels of par- asites were usually considered to reflect pulmonary coloniza- tion, but their significance was a subject of controversy. Cases of colonization were described mainly in patients positive for HIV who had blood CD4 1 T cell counts of /L (2). 6 ! 400 3 10 There were little data concerning HIV-negative patients (3). This study investigates the presence of P. carinii DNA in BAL fluid specimens from HIV-negative patients with no evidence of PCP and examines the link between colonization and decreases in blood CD4 1 T cell counts in this patient population.

Genotypes at the Internal Transcribed Spacers of the Nuclear rRNA Operon of Pneumocystis jiroveci in Nonimmunosuppressed Infants without Severe Pneumonia

ABSTRACT The frequency of Pneumocystis jiroveci (human-derived Pneumocystis) in immunocompetent infants developing acute respiratory syndromes has recently been evaluated and has been shown to be close to 25%. Until now, there have been no data on the genomic characteristics of the fungus in these patients, while molecular typing of P. jiroveci organisms was mostly performed with samples from immunosuppressed patients with pneumocystosis (Pneumocystiscarinii pneumonia [PCP]). The present report describes the genotypes of P. jiroveci organisms in 26 nonimmunosuppressed infants developing a mild Pneumocystis infection contemporaneously with an episode of bronchioloalveolitis. The typing was based on sequence analysis of internal transcribed spacers (ITSs) 1 and 2 of the rRNA operon, followed by the use of two typing scores. By use of the first score, 11 P. jiroveci ITS types were identified: 10 were previously reported in immunosuppressed patients with PCP, while 1 was newly described. By use of the second score, 13 types were identified, of which 2 were newly described. The most frequent type was identified as type B1a3 (first score), which corresponds to type Eg (second score). Mixed infections were diagnosed in three infants. The occurrence of such diversity of P. jiroveci ITS types, an identical main type, and mixed infections has previously been reported in immunosuppressed patients with PCP. Thus, the P. jiroveci ITS genotypes detected in immunocompetent infants and immunosuppressed patients developing different forms of Pneumocystis infection share characteristics, suggesting that both groups of individuals make up a common human reservoir for the fungus. Finally, the frequency of P. jiroveci in nonimmunosuppressed infants with acute respiratory syndromes and the genotyping results provide evidence that this infant population is an important reservoir for the fungus.

Pneumocystis carinii detection using nested-PCR in nasopharyngeal aspirates of immunocompetent infants with bronchiolitis.

Sero-epidemiological data indicate that first contacts with Pnewnocysris carinii (P. carinii) occur in more than 90% of immunocompetent infants before 2 years of age [l]. Until recently. primary infection by P. carinii was thought to be essentially asymptomatic [6 ] . In fact, there is little data concerning clinical profiles related to primary infection occurring in inununocompctcnt infant populations [3]. Indeed, for ethical reasons it is difficult to carry out prospective studies among healthy infants. Several infants and preschool children presenting acute respiratory illness related to bronchiolitis are hospitalized each year in our hospital (University Hospital, Amiens, France). Nasopharyngcal aspirates (NPAs) are routinely performed in this patient population in order to diagnose viral and bacterial infections. However, the specimens are not usually examined for P. carinii. We hypothesized that some of these pulmonary syndromes could be due to P. carinii infection. To test this hypothesis, all NPAs obtained from immunocompctent infants and preschool children with acute pulmonary syndrome who were admitted to our hospital over a 2-year period, were examined for P. carinii. The aim of this study was to desaibc the dctcction of P . carinii in NPAs from immunocompetent infants diagnosed with bronchiolitis.

Pneumocystis jiroveci Dihydropteroate Synthase Genotypes in Immunocompetent Infants and Immunosuppressed Adults, Amiens, France

To date, investigations of Pneumocystis jiroveci circulation in the human reservoir through the dihydropteroate synthase (DHPS) locus analysis have only been conducted by examining P. jirovecii isolates from immunosuppressed patients with Pneumocystis pneumonia (PCP). Our study identifies P. jirovecii genotypes at this locus in 33 immunocompetent infants colonized with P. jirovecii contemporaneously with a bronchiolitis episode and in 13 adults with PCP; both groups of patients were monitored in Amiens, France. The results have pointed out identical features of P. jirovecii DHPS genotypes in the two groups, suggesting that in these two groups, transmission cycles of P. jirovecii infections are linked. If these two groups represent sentinel populations for P. jirovecii infections, our results suggest that all persons parasitized by P. jirovecii, whatever their risk factor for infection and the form of parasitism they have, act as interwoven circulation networks of P. jirovecii.

Pneumocystis jiroveci Internal Transcribed Spacer Types in Patients Colonized by the Fungus and in Patients with Pneumocystosis from the Same French Geographic Region

ABSTRACT Pneumocystis jiroveci (human-derived Pneumocystis) infections can display a broad spectrum of clinical presentations, of which pulmonary colonization with the fungus may represent an important part, occurring frequently in patients with various underlying diseases and presenting alternative diagnoses of acute pneumocystosis (Pneumocystis carinii pneumonia [PCP]). There are few data concerning the P. jiroveci genotypes involved in pulmonary colonization, whereas several genotypes responsible for PCP in immunocompromised patients have been described. In this study, P. jiroveci genotypes have retrospectively been investigated and compared in 6 colonized patients and in 11 patients with PCP who were in the same hospital. Seventeen archival bronchoalveolar lavage samples were genotyped at internal-transcribed spacer 1 (ITS1) and ITS2 of the nuclear rRNA operon. Fourteen different genotypes were identified, of which 1 was found only in colonized patients, 10 were found only in patients with PCP, and 3 were found in both patient populations. Mixed infections were diagnosed in 2 of the 6 colonized patients and in 6 of the 11 patients with PCP. The results show that similar genotypes can be responsible for PCP as well as pulmonary colonization. There is a high diversity of genotypes in colonized patients and in patients with PCP. Mixed infections may occur in these two patient populations. These shared features of P. jiroveci ITS genotypes in colonized patients and patients with PCP suggest that human populations infected by P. jiroveci, whatever the clinical manifestation, may play a role as a common reservoir for the fungus.

Immunocompetent Infants as a Human Reservoir for Pneumocystis jirovecii: Rapid Screening by Non-Invasive Sampling and Real-Time PCR at the Mitochondrial Large Subunit rRNA Gene

ABSTRACT. We tested a real‐time PCR assay targeting the Pneumocystis jirovecii mitochondria1 large subunit rRNA gene on 240 archival nasopharyngeal aspirates from non‐immunosuppressed infants. The sensitivity of this assay appeared close to that of a conventional nested‐PCR assay targeting the same locus. Because of its one‐step procedure, and its sensitivity and rapidity, the real‐time PCR assay is particularly suitable for screening individuals parasitized by P. jirovecii within large populations.

Pneumocystis jiroveci Genotypes and Primary Infection

This study describes the molecular typing of Pneumocystis jiroveci organisms from 5 nonpremature immunocompetent infants who developed a primary infection. Four P. jiroveci internal transcribed spacer (ITS) types were identified. All have been previously described in reports concerning immunosuppressed adults with pneumocystosis. Present data suggest that identical types can be implicated either in first contact or in additional contacts between fungus and host and that both immunocompetent infants and immunocompromised patients may be part of a common human reservoir for the fungus.

Malaria elimination in Haiti by the year 2020: an achievable goal?

Haiti and the Dominican Republic, which share the island of Hispaniola, are the last locations in the Caribbean where malaria still persists. Malaria is an important public health concern in Haiti with 17,094 reported cases in 2014. Further, on January 12, 2010, a record earthquake devastated densely populated areas in Haiti including many healthcare and laboratory facilities. Weakened infrastructure provided fertile reservoirs for uncontrolled transmission of infectious pathogens. This situation results in unique challenges for malaria epidemiology and elimination efforts. To help Haiti achieve its malaria elimination goals by year 2020, the Laboratoire National de Santé Publique and Henry Ford Health System, in close collaboration with the Direction d’Épidémiologie, de Laboratoire et de Recherches and the Programme National de Contrôle de la Malaria, hosted a scientific meeting on “Elimination Strategies for Malaria in Haiti” on January 29-30, 2015 at the National Laboratory in Port-au-Prince, Haiti. The meeting brought together laboratory personnel, researchers, clinicians, academics, public health professionals, and other stakeholders to discuss main stakes and perspectives on malaria elimination. Several themes and recommendations emerged during discussions at this meeting. First, more information and research on malaria transmission in Haiti are needed including information from active surveillance of cases and vectors. Second, many healthcare personnel need additional training and critical resources on how to properly identify malaria cases so as to improve accurate and timely case reporting. Third, it is necessary to continue studies genotyping strains of Plasmodium falciparum in different sites with active transmission to evaluate for drug resistance and impacts on health. Fourth, elimination strategies outlined in this report will continue to incorporate use of primaquine in addition to chloroquine and active surveillance of cases. Elimination of malaria in Haiti will require collaborative multidisciplinary approaches, sound strategic planning, and strong ownership of strategies by the Haiti Ministère de la Santé Publique et de la Population.

Seroprevalence of human Taenia solium cysticercosis in Haiti.

Human Taenia solium cysticercosis is common in developing countries due to poor sanitary conditions and economics based on breeding livestock, especially pigs, with low hygiene standards. Neurocysticercosis, caused by migration of the larvae of the tapeworm in the nervous system, is the leading cause of acquired epilepsy in adults in Central and South America, sub-Saharan Africa, and East and South Asia. This makes neurocysticercosis a large public health problem in developing countries. Two clinical cases of neurocysticercosis have been observed recently in Haiti. In order to evaluate the prevalence of human T. solium cysticercosis in this country, in 2007 we conducted a cross-sectional serological retrospective survey using a Western blotting test (LDBIO Diagnostics) in Port-au-Prince, where sewage systems are rare and swine usually roam freely throughout the area. A total of 216 serum samples, obtained from healthy adults seen in the work setting of periodical medical visits, were tested after storage at - 20 degrees C. The frequency of antibodies in serum samples of the study population was 2.8% (6/216). The immunodominant bands recognized in Western blots were 23-26 kDa (100%), 39 kDa (67%), 45 kDa and 6-8 kDa (50%), 50-55 kDa (33%). These results confirm for the first time an endemic situation of cysticercosis in humans in Haiti, with similar prevalence as that reported in other Latin American and African countries. It reinforces the urgent need for control and prevention measures to be taken by local public health services.

The emergence of Trichophyton tonsurans in Port-au-Prince, Haiti

The occurrence of the anthropophilic dermatophyte Trichophyton tonsurans as a frequent causative agent of tinea capitis in several developed countries has been associated with a global rise in its isolation during recent years. While T. tonsurans was never found in Haiti before 1988, a sharp increase in the number of isolates of this species from scalp lesions began to be observed in 2005 in Port-au-Prince, Haiti. A prospective study was conducted in Port-au-Prince from May to November 2006 of 64 children presenting with tinea capitis at the dermatological outpatient clinic of the university hospital. Forty-five (70%) were male and 19 female (30%), with an average age at presentation of 6.1 years (age range 1-16 years). Direct microscopic examination of scalp hair using 10% potassium hydroxide was positive in 93.8% and culture confirmation was established in 55 cases (85.9%). Five species of dermatophytes were identified, with the anthropophilic dermatophyte T. tonsurans, accounting for the majority or 35 (63.6%) of all cases of tinea capitis. Other dermatophyte species identified included T. mentagrophytes (14.5%), Microsporum audouinii (12.7%), T. rubrum (7.3%) and in one case, the geophilic M. gypseum (1.8%). In two cases caused by T. tonsurans skin involvement on other areas of the body was recorded. The most frequent pathogen in tinea capitis is now T. tonsurans in Port-au-Prince. We speculate that the recent emergence of T. tonsurans in Haiti is linked to the dramatically increasing mobility of Haitian Diaspora.